U.S. patent number 4,150,781 [Application Number 05/752,912] was granted by the patent office on 1979-04-24 for access authentication system.
Invention is credited to Everett A. Johnson, Daniel Silverman.
United States Patent |
4,150,781 |
Silverman , et al. |
April 24, 1979 |
Access authentication system
Abstract
This invention describes a system for access control, wherein a
control card is presented to a control means. If the control card
is authenticated, then access is gained. If it is not
authenticated, access is not gained, the control card is retained,
and an alarm may be sounded. The control card contains at least two
means; (1) machine readable indicia identifying the card, and (2) a
random pattern of micro spots, which pattern is derived (by direct
copying--such as by focussed laser beam) from one of a plurality of
different patterns, retained in a bank of such micro patterns, each
such micro pattern identified by, and selectable in accordance
with, different unique indicia, identical with the machine readable
indicia on said cards. In use the control card is introduced into
the control means and the indicia are read. Master micro pattern
corresponding to the indicia is selected from the bank. The card
micro pattern and master micro pattern are compared. If the
comparison okay, the card is authenticated.
Inventors: |
Silverman; Daniel (Tulsa,
OK), Johnson; Everett A. (Park Ridge, IL) |
Family
ID: |
23969379 |
Appl.
No.: |
05/752,912 |
Filed: |
December 21, 1976 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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495632 |
Aug 8, 1974 |
3999042 |
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272739 |
Jul 18, 1972 |
3829661 |
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74066 |
Sep 21, 1970 |
3677465 |
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Current U.S.
Class: |
235/382; 235/457;
235/489; 250/566; 235/459; 235/493; 359/2; 359/11 |
Current CPC
Class: |
G07C
9/20 (20200101); G06K 19/14 (20130101); G07F
7/086 (20130101) |
Current International
Class: |
G07C
9/00 (20060101); G07F 7/08 (20060101); G06K
19/14 (20060101); G06K 005/00 (); G06K 007/10 ();
G06K 019/06 (); G06K 021/00 () |
Field of
Search: |
;235/61.11E,61.7B,61.7R,454,456,457,458,459,460
;250/555,566,568 |
References Cited
[Referenced By]
U.S. Patent Documents
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|
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3829661 |
August 1974 |
Silverman et al. |
3999042 |
December 1976 |
Silverman et al. |
|
Primary Examiner: Cook; Daryl W.
Parent Case Text
CROSS REFERENCE TO RELATED PATENT AND APPLICATIONS
This application is a continuation in part of copending application
Ser. No. 495,632, filed Aug. 8, 1974, now U.S. Pat. No. 3,999,042,
as a division of our antecedent application Ser. No. 272,739, filed
July 18, 1972, now U.S. Pat. No. 3,829,661, entitled ACCESS CONTROL
SYSTEM, which in turn is a continuation in part of our earlier
application Ser. No. 74,066, filed Sept. 21, 1970, entitled METHOD
AND APPARATUS FOR AUTHENTICATION OF INFORMATION RECORDS, now U.S.
Pat. No. 3,677,465.
Claims
We claim:
1. A system for access control, for selectively granting access on
presentation and authentication of a control token, said system
comprising:
A. a bank comprising
(1) magnetic storage means for storing a plurality of unique
authenticating master coded magnetic bit patterns, each in
different address locations;
(2) a plurality of address locations in said magnetic storage
means, each address being an index of the magnetic bit pattern
stored therein;
B. a plurality of control tokens, each control token comprising
(1) an unique object;
(2) means on said object for storing in machine readable form an
unique index;
(3) means on said object for storing in machine readable and
machine writeable form an unique coded bit pattern of magnetically
altered areas;
(4) each of said control tokens having one of said unique indicia
and the corresponding unique authenticating coded magnetic bit
patterns stored in said bank;
C. reading means to which a control token can be presented, said
reading means including first means to read said indicium, and
second means to read said magnetic bit pattern on said token;
D. means responsive to said first means to select from said bank
said magnetic bit pattern corresponding to said indicium;
E. means to compare the magnetic bit pattern read from said token
with the magnetic bit pattern in said bank corresponding to the
read indicium;
F. means to produce a plurality of unique magnetic bit patterns;
and
G. means responsive to said comparison means to select a different
unique magnetic bit pattern from said means to produce, and to
write a new unique bit pattern on said token and in said bank in an
address corresponding to said indicium on said token.
2. The system as in claim 1 in which said second means includes
means to relatively scan a magnetic reading and writing means along
said token over said magnetically altered areas.
3. The system as in claim 1 in which said second means includes a
plurality of individual magnetic sensor elements in fixed linear
array, which array is congruant with the array of bits in said bit
pattern.
4. The system as in claim 3 and including means to relatively
oscillate said array of sensors and said token, in the direction of
said array, whereby bit signals will be generated in said sensors
in accordance with said bit pattern.
5. The system as in claim 3 and including means to demagnetize said
magnetizable material.
6. The system as in claim 5 including means after said magnetizable
material is demagnetized, and said relative oscillation is stopped,
of applying a writing signal to a selected number of said plurality
of elements to record a new bit pattern on said magnetizable
material.
7. An access control system utilizing optical holograms, for
selectively controlling access on presentation and authentication
of a control card to said system comprising:
A. a bank containing a plurality of unique authenticating master
patterns for coding a reference beam;
B. each of said master patterns stored in a bank in relation to one
of a plurality of unique indicia;
C. a plurality of control cards, each card having one of said
plurality of unique indicia, and also having one of said optical
holograms which was recorded by an object beam of at least one
unique spot pattern, and a coded reference beam having a coding
pattern stored in said bank corresponding to said unique
indicium;
the improvement in means for authenticating said control card when
presented to gain access, comprising
D. means for reading said indicium on said card;
E. responsive to said reading of said indicium, means to select
said reference beam coding pattern stored in said bank
corresponding to said indicium;
F. means for coding a reference beam with said selected reference
beam coding pattern, and for reconstructing said hologram on said
card, to provide an image of said at least one unique spot pattern
of said object beam.
8. The system as in claim 7 including a bank containing a plurality
of unique spot patterns for coding said object beam, each pattern
stored in relation to a second unique index, corresponding to a PIN
number entered at the time said card is presented; and means to
compare said reconstructed image with said object beam spot pattern
selected by said PIN number.
9. An access control system utilizing holograms for selectively
controlling access on presentation and authentication of a control
card to said system, comprising
A. a bank containing a plurality of unique authenticating master
spot patterns for coding object beams;
B. each of said object beam coding patterns stored in a bank in
relation to one of a plurality of unique indicia;
C. a plurality of control cards, each said card having one of said
plurality of unique indicia, and also having an optical hologram,
which was recorded by an object beam which was coded by one of said
plurality of unique spot patterns, and a coded reference beam, the
coding pattern of said reference beam also recorded on said
card;
the improvement in means for authenticating said control card when
presented to gain access comprising
D. means for reading said indicium on said card;
E. responsive to said reading, means for selecting the proper
object beam coding pattern corresponding to said index;
F. means for passing a coherent beam of radiation through the
reference beam coding pattern on said card, to form a coded
reference beam, and means for irradiating said hologram on said
card with said coded reference beam to reconstruct said hologram
and form a reconstructed image of the object beam coding pattern,
and
G. means for comparing the spot pattern of said reconstructed image
with said selected object beam coding pattern.
10. The system as in claim 9 including means to relatively rotate
the plane of said card with respect to the direction of said coded
reference beam by a selected angle of rotation in azimuth and
elevation.
11. A system for access control, for selectively granting access on
presentation and authentication of a control token, said system
comprising:
A. a bank comprising
(1) storage means for storing a plurality of unique authenticating
master coded bit patterns, each in different address locations and
comprising magnetically altered areas;
(2) a plurality of address locations in said storage means, each
address being an index of the bit pattern stored therein;
B. a plurality of control tokens, each control token comprising
(1) an unique object;
(2) means on said object for storing in machine readable form an
unique index;
(3) means on said object for storing in machine readable and
machine writeable form an unique coded bit pattern;
(4) each of said control tokens having one of said unique indicia
and the corresponding one of said unique authenticating coded bit
patterns stored in said bank;
C. reading means to which a control token can be presented, said
reading means including first means to read said indicium, and
second means to read said coded bit pattern on said token;
D. means responsive to said first means to select from said bank
said coded bit pattern corresponding to said indicium;
E. means to compare the unique bit pattern read from said token
with the stored bit pattern in said bank corresponding to the read
indicium;
F. means to produce a plurality of unique bit patterns; and
G. means responsive to said comparison means to select a different
unique bit pattern from said means to produce, and to write a new
unique bit pattern on one of said tokens and in said bank in an
address corresponding to said indicium on said token.
Description
A related patent is our U.S. Pat. No. 3,818,190, granted June 18,
1974, on our application Ser. No. 272,686, filed July 17, 1972,
entitled AUTHENTICATION OF ACCESS TO INFORMATION RECORDS.
BACKGROUND OF THE INVENTION
This invention is in the field of control cards for gaining access.
More particularly it is for gaining access to a restricted area, or
access to restricted material or papers, or access to money,
tickets, checks and the like.
In the prior art there have been many types of control cards
described. All of these attempt, in one way or another, to provide
some crucial test, which can be preformed on the card so as to
determine whether it is authentic, or a copy or forgery. All of the
physical properties of the prior art cards were capable of being
copied, and therefore the tests of validity or authentication were
of little value.
SUMMARY OF THE INVENTION
It is a principle object of this invention to provide an access
control system which is selective and which is extremely difficult
or impossible to duplicate. It is a further object of this
invention to provide an access control system which is self
protective in that it has plural means to detect forgeries.
These and other objects are realized and the limitations of the
prior art devices are overcome in this invention, in which the
authentication is obatined by precise comparison of a random spot
pattern with an identical one, from which the first one was
derived. The spots in the pattern are microspots, too small to be
seen with the naked eye, and recorded in a suitable sheet material
by copying through microperforations in a master micro pattern, by
means of a focussed laser beam.
Because of the extremely small size of the spots, the pattern can
not be copied by a stop-position-print system.
Furthermore the sheet material must have a thickness and melting
point such that it will withstand, without melting, the passage of
a focussed laser beam of a selected intensity.
The pattern can not be copied photographically, since the
photographic material will not withstand the laser beam.
The pattern can not be copied photographically and etched, since
the microperforations will not be of the correct size.
They can only be copied from the master pattern by passage of a
focussed laser beam over the microperforations in the master
pattern card.
In the use of the control card, it is inserted into control
unit.
It is then advanced to a first station where the indicia are read.
At this point the indicia are compared to a prior list of indicia
which are indicated as unacceptable. If the indicia are okay it
then goes to the second station.
At the Second Station the card is scanned by a focussed laser beam
of a specified intensity level. This level is just below the level
which will burn the pattern sheet of the valid cards. If the
pattern sheet of the card is not burned, as evidenced by a
photoelectric system for detecting major perforations in the
pattern sheet, the card then goes to the third station.
At the Third Station the micro pattern on the card is compared to a
selected master pattern which corresponds to, and has been selected
from a bank of master patterns in accordance with the indicia read
from the card.
Two tests are made at this station. The first is to compare the
pattern on the card with the master pattern. If this checks, then
the second test is made.
In the second test, the sizes of the microperforations in the
pattern sheet are compared to the size of the microperforations in
the master card. This can be done by slowly shifting the position
of one pattern with respect to the other, at a selected constant
speed, and measuring the time that light passes through any
selected spot, as plurality of spots.
If the card passes this test, then it is considered authentic and
the appropriate operative mechanism is activated to provide the
access requested. Also the card is returned to the owner who first
inserted into the control apparatus.
Not all of these tests may be required. The principal test, is of
course, the comparison of the patterns in station 3 test (a), the
master pattern having been selected on the basis of indicia read in
the First Station. Also, other tests may be provided, including,
for example, comparing a photograph on the card with the person
presenting the card, or comparing finger prints, etc.
BRIEF DESCRIPTION OF THE DRAWINGS
These and other objects of this invention and a better
understanding of the principles and details of the invention will
be evident from the following description taken in conjunction with
the appended drawings, in which:
FIG. 1 illustrates a type of access card useful in this system.
FIG. 2 illustrates the preferred embodiment of the access system of
this invention.
FIG. 3 illustrates the test for perforation size.
FIG. 4 illustrates an embodiment in which a key, token, or card is
provided, which has machine readable macroindicia and a bit pattern
of magnetically altered areas on a strip of magnetic material, and
a reading means.
FIG. 5 illustrates a system wherein a type of spot pattern can be
read statically by magnetic means.
FIG. 6 shows a typical prior art magnetic reading head moved along
a magnetic strip.
FIG. 7 shows record and read heads of simplified type in accordance
with our invention.
FIG. 8 illustrates schematically apparatus for the preparation of a
hologram, using a spot pattern object, and an amplitude coded
reference beam.
FIG. 9 shows a film strip means for coding reference beams.
FIG. 10 illustrates another embodiment in which the card carries a
unique machine readable index, a reference beam coding pattern, and
an object beam coded by a unique spot pattern of FIG. 5, selected
from a bank, such as that of FIG. 9.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the drawings, numeral 10 indicates generally the
card input station, numeral 12 indicates generally the First
Station, numeral 14 indicates computer apparatus to check the
indicia against a prepared list of indicia, numeral 16 indicates
the Second Station, numeral 18 the Third Station, 20 indicates the
pattern comparison means, 22 the operative means responsive to the
validation means, 24 the perforation size measurement means, 26 the
access control card, 28 the machine readable indicia on the control
card, and 30 the pattern of microperforations by means of which the
control card will be validated or authenticated.
This application is a continuation-in-part of our copending
application, Ser. No. 74,066, filed Sept. 21, 1970, entitled;
Method and Apparatus for Authentication of Information Records, now
U.S. Pat. No. 3,677,465, which is made part of this application, by
reference, and will be depended on for much of the detail of the
apparatus to be described.
Also, there will only be schematic diagrams given of the physical
apparatus, such as the case, the card handling means, and the
operative means which actually accomplishes the access. This
invention does not involve any specific means for housing the
electronic and photo apparatus, or the card handling apparatus, and
since there are a number of such devices described in the patent
literature, such as for example, U.S. Pat. No. 3,571,957, issued
Mar. 23, 1971, No. 3,620,590 issued Nov. 16, 1971, No. 3,629,834,
issued Dec. 21, 1971, and others, it is not deemed necessary to
describe the details of construction or operation, since those are
well known to one skilled in the art.
FIG. 1 indicates a card, token, sheet, web or other medium for
carrying the specific information required in this invention. For
convience, we will call this means a "card", although, as is well
known it can be in any one of many different forms.
There are two principal areas of the access control card, or access
card, or control card, or simply card 26, that carry important
information. The first space 28 carries indicia which are machine
readable. These can be perforations, or embossed characters
representing specific information, such as account number or name
and address of the card owner, or other information. The group of
characters 100, and spaces 102 that make up the indicia represent
specific information. The words indicia, or characters, will
represent the physical markings on the card, or the specific
information they uniquely represent. The indicia on each card
issued are all different, and associated with each indicia there is
a difficult unique pattern, which is marked on the card in a second
area 30.
The pattern 30 is made up of a random distribution of a plurality
of spots, which are microperforations in a thin opaque metal layer.
As described in our U.S. Pat. No. 3,677,465, the material 98 which
carries the pattern 30 can be a thin evaporated layer of metal or a
transparent base material such as clear plastic.
For each card carrying its unique pattern 30 there is an identical
master pattern of microperforations in a metal layer. This master
pattern can be a self supporting metal sheet or film, or a thin
metal coating on a transparent plastic base, etc. The
microperforations are preferably prepared in the master pattern by
means of a pulsed focussed beam of laser radiation of a selected
level L1 of intensity.
The patterns 94 in the sheets 98 are precise copies of the master
patterns made by superimposing the master pattern material on top
of the card material 98, and passing a continuous beam of focussed
laser energy through the microperforations in the master pattern,
to the underlying metal layer of the sheet 98, and burning
microperforations in the same pattern as in the master pattern.
As explained in U.S. Pat. No. 3,677,465 it is necessary that the
metal layer of the master pattern be of higher melting point,
and/or thicker, than the metal layer of the sheet 98 of the card.
Thus, when the intensity of the continuous focussed beam is set at
a value of intensity level L2 where L2 is less than L1, this beam
will not affect the metal of the master pattern, but will burn
holes in the sheet 98.
There is also a third intensity level L3, where L3 is less than L2,
which when scanned across the material 98 will not affect the metal
layer of the material 98.
On the record card 40 there may be other areas 95, 96, 97, etc.
Which may include the signature of the card owner, his picture, or
his fingerprint, or other identifying information, which can be
further used to authenticate the card and the bearer of the card.
Such additional information is well known in the art and forms no
part of this invention, and will not be described further.
Referring now to FIG. 2, the card of FIG. 1 is inserted into an
opening 32 in a casing 34 that houses a plurality of test or
measuring stations. As mentioned above, the particular housing, or
means of transport of the card, etc., form no part of this
invention and reference is made to the prior art for such
details.
The card entered at 32 is transported through passage 36 by means
38, well known in the art, to the First Station 12. Here the card
40 is presented with means 42, well known in the art, for reading
the markings 28, and determining the information corresponding to
the indicia. This information is sent to a computer means 46, which
when it receives the indicia read from the card compares the
indicia with a preselected list, bank or tape of indicia, to see if
that specific information is listed in the bank or on the tape.
This list could be, for example, all indicia on cards lost, stolen,
or otherwise declared invalid. If the specific indicia 93 is found
on that list, the card is rejected and falls into a receptacle
inside the housing (not shown). If desired, an appropriate notice
is given to the person who inserted the card, that it is invalid
and is being confiscated. At the same time the indicia read by 42
also goes by line 48 to the Third Station, for a purpose to be
described later.
If the indicia read by 42 is not on the list at 46, then the card
40 progresses to the Second Station 16. Here two tests are
performed. The first test is to check the nature of the material of
the sheet 98. A laser 52 passes light through an intensity control
means 54, via beam 56 to a mirror 58 and through an optical means
60 to focus the beam 62 onto the top surface of the material 98.
The intensity level is adjusted to the level L3, which is just
below the level L2, where it will burn the metal layer. With the
level at L3, the beam is scanned across the pattern 30, in
accordance with arrows 61.
If the material of the sheet 98 is not the proper material, for
example, if it is a photographic emulsion, then it will not support
the beam of intensity level L3, and parts or all of the opaque
material 98 will be burned away. When this happens, as the beam is
scanned in accordance with the arrows 61, openings in the opaque
layer will be formed.
The second test is then applied. This involves passing light from a
source 64 through lens 66, through the pattern area 30 and to a
photoelectric sensor 70. If no light passes, it indicates that the
material 98 is satisfactory. If light passes, it indicates that the
material 98 is a substitute material, and therefore the card is
invalid, and it is confiscated.
If the card 40 passes the tests at Station 2, it then goes to
Station 3. Here there is a bank of master patterns. These may be on
separate cards or sheets, or may conveniently be on a reel or strip
of material 76, with separate frames or areas, each having its
unique pattern of microperforations in the metal layer of the
strip. Corresponding to each frame, is an index, which corresponds
to the indicia of that pattern. Thus, when the First Station reads
the indicia, this information goes to control means 74. This
control means operates motors 77, 82, which drive reels 78, 81
respectively to position the proper frame, and pattern in an
aperture between the rollers 83, 84. Thus the correct master
pattern corresponding to the indicia on the card 40 is now
displayed in the aperture 87. The control means 74 can be
conventional, similar to the many examples of strip films or tapes
carrying micropatterns and digital indicia, with means to transport
the strip until a desired index is reached, etc.
The card 40 is now sent to the Third Station and positioned so that
the pattern 94 is precisely lined up in the aperture 87 so that the
two patterns, that is, the master pattern and the card pattern 30,
are aligned. Optical means 86, cooperating with sensor means 88
determine if the patterns are identical. If they are not identical,
the card 40 is discarded.
The materials of the master pattern and the card pattern are
specialized, in that the master material (metal) is of high melting
temperature and/or thicker, while the card material (metal) is
lower melting temperature and/or thinner. The patterns of
microperforations are copied and burned into the card metal by
focussed laser beam from the master material. The microperforations
in both materials are of exceedingly small size, so that the
patterns must be precisely positioned with respect to each other.
Reference is made to U.S. Pat. No. 3,677,465 for details on the
systems for comparing the two micropatterns. Normal digital reading
systems are not practicable since the spots are too small, and the
spacings are random. Misalignment of one microperforation by a
distance of the order of the diameter, (which may be as small as
0.0005 in.) will cause the comparison means 74 to reject the
card.
The purpose of the use of thin metal layers and microperforations,
and the transfer of patterns described, is to prevent forged copies
from being used. For example, the simplest way to copy the pattern
on a card is to make a photographic copy, and that copy (except for
changes in dimension) might be used in the comparator 74. However,
such a photographic copy will not stand the test of the laser of
intensity L3. The only material that will satisfy that test is a
metal of the same melting point and thickness as the material 98
used in the card. And the pattern cannot be transferred from the
card to the new material by photography. Nor can it be transferred
by laser, since the laser of intensity level L2 which would burn
microperforations in the new material would also destroy the card
material.
However, the pattern could be etched in a suitable metal by
photoetching. However, the size of the perforations would not
duplicate those of the master card, and this is the reason for the
next test.
In FIG. 2 the card 40 is shown connected to motor 104 by means 106.
When the motor 104 is started the card will pass at a constant
velocity past the master pattern on the strip. In FIG. 3 we have
shown (enlarged) the relationship between a microperforation 110 on
the master pattern as the corresponding microperforation 112 in the
card passes to the right, in the direction of arrow 120. When the
two are tangent at 114, light is just beginning to pass through the
two microperforations. Consider for simplicity, that the opening
110 is moving to the left. When the leading edge of 110 gets to
position 115, the two microperforations are completely
superimposed. Then when it gets to 116, there is no more light
passing. Thus the two patterns must be relatively traversed by a
distance from 114 to 116, equal to the sum of their diameters.
Now, consider that the card pattern has at least one perforation
122 that is oversize. Then the traverse must be over a distance
from 114 to 118, (again the sum of their diameters) which will be
larger than the distance 114 to 116. There are well known
techniques for measuring small distances, such as measuring time of
tranverse, etc., this would be done in means 92. Thus it will not
be necessary to provide more details since the specific means forms
no part of this invention.
If the pattern comparison is okay and the test of size is okay,
then the card will have passed all tests, and the card is validated
and the operative means 22 is energized to provide the requested
access. No detail is provided for the mechanism 22, which can be as
simple as a relay to open a locked gate, or as complicated as a
device for dispensing currency, providing access to a computer or
to a cable TV circuit, credit purchase, etc., since these specific
means form no part of this invention and are well know in the
art.
While we have indicated means to check the validation of the
pattern, and have indicated other means to test the authenticity of
the card itself, it will be clear that the apparatus can be
operated without carrying out all of the tests.
It will be clear also, that while we call the patterns or the strip
76 the "master patterns", these can be copies of other master
patterns in materials of still greater thickness and/or higher
melting point.
In the drawing, FIG. 2 illustrates the system as a plurality of
successive stations or operations on the control card. The area of
the card devoted to indicia is separate from the area devoted to
micropattern, and it is clear that the means to read and the means
to compare may be situated within the outer boundary of the card.
Thus the card need only be positioned in a single location.
Our disclosed invention includes an access control system for
selectively controlling access on presentation and authentication
of a control card. This card comprises card means, machine readable
indicia carried thereby, and unique coded micropattern means
thereon. The card authentication means comprises means to read the
indicia, and a bank of authenticating master coded micropatterns.
Selecting means, responsive to the means to read the indicia,
selects the master coded micropattern from the bank corresponding
to the coded micropattern on the card means; and means to compare
the coded micropatterns on said card means with the master
authentication micropattern selected from the bank in response to
the read indicia.
The system may further include operative means responsive to said
comparison means, said operative means including means to authorize
access when the compared patterns correspond. A preferred form
includes coded micropattern means comprising an array of
microperforations; and the coded micropattern means may include
redundant coded patterns.
The system as described above in which said card micropattern is
transferred from said master micropattern by focussed laser means
of intensity level L2; and including means to scan across said card
micropattern with a focussed laser beam of intensity level L3,
where L3 is less than L2.
The microperforations may be burned in said master pattern in a
metal layer of first melting point and first thickness by scanning
with a focussed laser beam of intensity level L0 through
microperforations in a supermaster pattern in a third mayer of
third melting point and third thickness, where L0 is higher than
L2.
Also the system includes means, responsive to said means to read
said indicia, to compare said indicia with a preselected list of
indicia; and the master micropattern is in a first metal alyer of
first melting point and first thickness, and said card micropattern
is in a second metal layer of second melting point and second
thickness, and said first melting point may be higher than said
second melting point and said first thickness may be greater than
said second thickness.
The system includes means to compare the sizes of the
microperforations in said card micropattern with the sizes of the
microperforations in the master pattern.
The fundamental basis of this invention lies in the use of a card
having a machine readable indicium and a unique pattern, and a bank
having a plurality of indicia and corresponding patterns, and means
responsive to the read indicium on the card to select the
corresponding pattern, and means to compare the selected pattern
and the card pattern.
In this invention the unique pattern is a micropattern of
microperforations which can not be read by eye, and not by machine,
except by the optical comparison with the bank pattern. To do this
the card must be presented where there is a bank of patterns.
Another method in which the pattern is unique and not readable
except by selection of a particular pattern in the bank, is to use
a photographic hologram on the card, and in the bank a
corresponding coded reference beam (see our U.S. Pat. No.
3,807,828). When the hologram on the card is exposed to the coded
reference beam, since the hologram was made with that specific
coded reference beam, the hologram will be reconstructed and an
image of the object of the hologram will be formed. This object
could be a point, or plurality of points, of light falling on PE
sensors, etc.
Both the hologram card and the micropattern card have great
security because of their permanent complex patterns which cannot
easily be duplicated. However, they have the limitation that they
must be presented adjacent a bank.
There is another type of pattern, such as a magnetic code pattern
or a machine readable card, that comprises a series of time spaced
pulses, or bit pattern. These can easily be transmitted from a
distant reading station to a bank (computer memory) for comparison
be well known digital means. However, the magnetic card pattern is
not secure, since anyone finding the card can read the pattern and
make a corresponding facsimile, by means of which they can enter
the bank. This system can be used at great distances from the bank,
but has the disadvantage of poor security.
The security can be greatly improved by changing the pattern on the
card and in the bank each time the card is used. Thus, the pattern
is continually being changed from one to another unique bit
pattern, so that a copied card cannot be used unless it is
presented before the next use of the original card. Also, the
unauthorized use is quickly detected because once the unauthorized
card is used, the true or original card cannot be used since the
pattern in the bank has been changed, by the use of the authorized
card.
While the invention has been described with a certain degree of
particularity it is manifest that many changes may be made in the
details of construction of the arrangement of components, it is
understood that the invention is not to be limited to the specific
embodiments set forth herein by way of exemplifying the invention,
but the invention is to be limited only by the scope of the
attached claim or claims, including the full range and equivalency
to which each element or step thereof is entitled.
Embodiments of our invention include an access security system for
monitoring access by authentication of a control member on
presentation which includes a bank of unique authenticating master
coded micropatterns of micro altered areas of web means, together
with a corresponding group of macropatters of machine readable
indicia, each of the macro indicia corresponding to selected
micropatterns and providing an index thereto, and a plurality of
control members, each such member having at least one of said
macropatterns of machine readable indicia and the corresponding
coded micropattern of micro altered areas. Means are included for
authenticating the presented control member, such means comprising
means for reading the macro patterns, means responsive to the
reading means, including means for selecting the corresponding
micropattern from said bank indexed by said macro indicia; and
means for comparing the micropattern on said member with the
indexed micropattern in said bank.
The disclosed access security system may also include means for
authorizing access when the compared micropatterns correspond; and
means for the delivery of an item identified by the coded
micropattern, and wherein the item delivered may comprise
currency.
Further embodiments of our invention include means for comparing an
array of at least two micropatterns on the control member, and
wherein the macro indicia indexes a corresponding series of
micropatterns in the bank; also the micropattern of micro altered
areas may comprise an holographic record, with the holographic
record being, for example, a photographic hologram adapted to be
reconstructed by a coded reference beam.
Another improved access security system includes a plurality of
micropatterns in a first array on a control member, means for
recognizing the array of micropatterns present, means for reading
the micropatterns in the array, and means for substituting for at
least one of said micropatterns another micropattern from said bank
to provide a second array, whereby the coded security access
afforded by the unique control member is revised on each authorized
presentation of said member.
A further feature of our access security system is one wherein the
micropattern of micro altered areas comprises a series of magnetic
spots, and the additional means for changing the arrays thereof on
the control member and for recording the change in the bank, the
changes being indexed by the macro indicia recognition.
An additional embodiment provides a further means for changing the
pattern on the control member and in the bank each time the member
is presented, whereby the micropattern is sequentially changed from
one to another unique master coded micropattern, thereby precluding
the unauthorized use of a facsimile after the next authorized
presentation of the original member.
The sequential changes are recorded in the bank and can provide a
record of presentations and transactions, and in addition provide a
means for security updating of the control member whether or not a
transaction is involved.
Referring now to FIG. 4, there is shown an embodiment in which a
key, token, or card 224 is provided, which has machine readable
macroindicia 226, and a bit pattern of magnetically altered areas
on a strip of magnetic material 228, applied to one surface of the
token, key or card 224. The overall card, plus reading means is
indicated generally by the numeral 210.
There are many words such as token, key, card, etc. which can be
used to identify the object which can be used to gain access. Such
objects can be of many different forms, some more suited to certain
conditions than to other conditions. One of the most common type of
object is a thin stiff card of paper or plastic, and this
invention, for convenience, will be described in terms of a card.
This in no way constitutes a limitation of the form in which the
article, or object, can be used.
The magnetic material 228 is generally applied in the form of a
thin layer of magnetic particles, applied to one surface of the
card. Such magnetic strip cards are widely used in industry and
need not be further described. Also, card readers have been in use
to read magnetized bit patterns previously impressed on the strip.
Such readers can utilize a conventional magnetic head assembly with
one or more heads reading one or more tracks which are moved along
the strip and sequentially read the bit patterns on the one or more
parallel tracks.
Other types of magnetic recording areas have been used in industry,
and can be used in this invention. One of the common types is a
circular area, which has a central perforation which serves to
position the axis of a rotating head mechanism.
The important point is that a record is provided in which
information in the form of a sequential bit pattern can be written,
read, and erased and another pattern written, and so on. The bit
pattern represents in binary decimal, or other digital form, a
unique number, which is applied to only one card, and is also
stored in a bank, or memory 272 in a mini-computer 212 for example.
The address in the memory or bank 214 in which that specific number
is stored, is the same as the index 226 recorded on the card
224.
Shown in FIG. 4 is the card 224 with index 226 and index reading
means 230. Also shown is the magnetic strip or record 228 and the
magnetic reading means 232. In general, as shown in FIG. 2, the
reading (or comparing) means is in a card handling reading means,
adjacent to the position in the card handling means where the card
is placed.
In FIG. 4 the rectangle 212 represents a control processing unit or
a CPU of a digital computer. It can be a large computer, or an
operating terminal of a large computer, or it can be a
minicomputer, as is well known in the art.
As peripheral equipment to the CPU (Central Processing Unit) or as
elements of the CPU, there is a memory or bank 214 for storing the
plurality of unique magnetic bit patterns, or numbers, in storage
areas, the addresses of which correspond to the macroindicia on the
cards, which carry the corresponding bit patterns.
There is another memory 218 which comprises a storage area for a
large number of random or unique numbers, or bit patterns. While
this can conveniently be a storage for such numbers, it also can be
an arithmetic unit that can calculate random or unique numbers.
There is a means to compare two unique bit patterns 216, which
would generally be a part of the arithmetic unit.
There is a means to grant access 220. This can be a remotely
operated door latch, or a means to deliver an object from storage
in a sales equipment, etc. The objects delivered or sold can be of
various types, such as food products, etc. They can also be packets
of money, or they can be means to transfer money from one account
to another, and so on.
All of these types of activity have been done in the prior art, and
commercial equipment is available to these operations subject only
to an appropriate electrical signal delivered over means 245.
As previously described, there may also be means 222 to confiscate
the card, if under selected circumstances, the card fails to meet
certain security requirements.
The equipment shown in FIG. 4 is divided into 3 main parts, defined
by dashed outlines 262, 264 and 266. While these may all be at the
same location, and even be in a single housing, the system is such
that it can be broken into parts such as the three parts
outlined.
The dashed outline 262 is the card reading area and includes means
to insert a card (as in FIG. 1) 230 to read the macroindicium 226,
means 232 to read the magnetic bit pattern on strip 228, and it may
contain means 222 to confiscate the card.
The dashed outline 266 is the means to grant access, and may be
positioned at any selected point. In fact there may be many such
points where access is to be granted.
The dashed outlines 266 and 262 may be combined. That is, the point
at which access is gained can be the point where the card 224 is
presented, or they can be at different points.
There may be at the position 262 where the card 224 is presented a
means 268 for data entry (DE), that is, for entry of numerical
data, such as the number corresponding to that at the point at
which access is desired. It will be clear also that the data entry
means 268 can be used to enter a PIN number, or "personal
identification number", by means of which an additional stage of
security can be provided.
The dashed outline 264 represents the control means, or CPU, of the
system. It will be clear also, that since, in the prior art,
computers have been used with large numbers of "terminals", or
points where the computer can be accessed, so too, it is possible
to have a plurality of boxes 266, representing distant distinct
locations where cards can be presented to gain access.
While we speak of gaining access, that is a very generalized term
for what can be accomplished with this system. It may, for example
be used to actually gain access through a door or gate. It may gain
access to any one of a plurality of small storage compartments
where articles are stored, such as for sale, such as products or
food items, etc. It may be used to gain access to a selected
account in a bank, from which money is to be delivered, and an
account debited, or it can be the means for controlling transfer of
funds from or to a first account, to or from another account, the
number of which can be indicated by entry through the data entry
means 268, and so on. It can also be used to authenticate a request
to gain access to a data bank in a computer from which, when the
card is authenticated, data can be reads from that data bank and
transferred to another computer, for example.
In this system the purpose is to present a card representing a
selected person or account, to have the card authenticated, and
when the authentication is completed, have one or more different
selected operations carried out.
Such cards have been used in the past, but the security has been
poor. For example, having a signature which is examined by eye. Or
the security may be dependent only on a PIN number which is punched
in by hand into a data entry unit such as 268. Once the PIN number
is learned by another person, there is no further security.
In this invention, a much more unique security means is utilized,
so that even if the numbers on a card are copied, or a facsimile
card is made, the facsimile card can not be used to gain access
unless it is presented before the next time that the true card is
presented. The unique coded master number is changed on the card
224 and in the bank 214 each time the card is presented and
authenticated. If the true owner presents his card and it is
authenticated, he knows that no facsimile card has been presented,
and also, any previously prepared facsimile card will become
ineffective, since the number in the bank has been changed. This
will be clear as the description proceeds.
In FIG. 4 the index reader 230 is connected to the computer 264,
and in particular to the CPU 212, by lead 234. The index number
read by 230 goes by lead 234 to the bank memory 214 via lead 236.
The binary coded magnetic bit pattern stored in the memory 214 at
the address transmitted on lead 236, is returned to the CPU over
lead 238. This unique authenticating master coded bit pattern goes
by lead 240 to a means to compare or comparator 216.
At the same time, the reading of the binary magnetic bit pattern
stored on the strip 228 read by 232 goes by lead 254 to the CPU and
by lead 256 to the comparator 216. If the numbers are identical, a
signal is sent over the "yes" line 242 and 245 to the means to
grant access 220, and the desired operation is carried out, the
desired operation having been indicated to the CPU (in case there
is morethan one) by the data entry means 268.
The "yes" signal over 242 goes also over lead 243 to the memory or
table of unique bit patterns, or numbers, 218. A new number is
selected and returned by line 248 to the CPU and by line 252 to the
write head 232 to be recorded on the magnetic strip 228. The new
number also goes by line 250 to be entered into the memory or bank
214 in the address location corresponding to the index 226.
The card and the bank have now been updated with new identical
unique numbers. The next time that the card 224 is presented and
authenticated another unique master bit pattern or number will be
supplied, and so on.
If the means to compare 216 finds, on comparison, that the number
from the bank on 240 does not agree with the number on 256 from the
card, a "no" signal is sent by way of lines 244 and 258 to the
means 222 to confiscate the card. The card is then held in the
instrument housing and not returned.
If it is assumed that the card 224 is stolen, or is "borrowed" and
the index 226 copied, and the bit pattern is copied onto another
card, to form a facsimile card. Such a facsimile card can be used
to gain access, only if it is presented before the next
presentation of the true card 224. If the true card is presented
first, and authenticated, then the number in the bank will be
changed. Then when the facsimile card is presented, it will not be
authenticated, but will be confiscated.
On the other hand, if the facsimile card is presented before the
next presentation of the true card 224, it will be authenticated
and its number and the bank's number will be updated. Thus the next
time the true card is presented, it will not be authenticated, but
will be confiscated. This in itself will be indication that a
facsimile card exists. The card owner must then present himself
with proper identification to get a new card. Until that time,
however, he must report the situation and ask that the number in
the bank be changed to ensure that further use of the facsimile
card will be prevented.
Security can be maintained by presenting the card at frequent
intervals, so that the number in the bank will changed at frequent
intervals, and thus hinder the use of a possible facsimile
card.
The indicium 226 can be one of many types such as:
(a) a line/bar printed pattern, such as are used on various product
packages in stores. The pattern can be read by the optical scanners
such as have been developed and manufactured to read these
patterns.
(b) an embossed pattern on a non magnetic card, read by
electromechanical means, as in the prior art.
(c) perforations in a spot pattern read optically.
(d) a permanent magnetic pattern such as illustrated in FIG. 5, and
others.
In FIG. 5 is shown a type of spot pattern that can be read
statically by magnetic means. There is a non-magnetic paper, or
plastic card 280. This has a thin layer or film of magnetic
material 282, such as a thin foil of iron, or such. This is
perforated in a spaced pattern by means of "perforations" 284 and
"non perforations" 286, at a selected spacing 297. There are a
plurality of thin rod-like magnetic cores 288A, 288B etc. at the
same spacing 297. An a.c. current of selected frequency is applied
from oscillator 292 through leads 293,295, switch 294 to each of
the coils 290A, 290N, etc. An ammeter can be used to indicate the
current that flows when a selected voltage is applied to the coil.
The impedance of the coil will vary depending on whether a
perforation or a nonperforation is present at the end of the core.
The impedance differences on the coils is dependent on the pattern,
and the pattern can be read by measuring the current or voltage,
and by other similar means as is well known in the art. The
impedance can be measured either simultaneously or
sequentially.
In FIG. 6 is shown a typical prior art magnetic reading head 300
which is pressed in contact with strip 298 of magnetic material on
one surface of the nonmagnetic card 280. Normally the head is moved
along the strip at a selected constant rate in accordance with
arrow 308A and pulses of current applied to the windings 304A and
304B to create a flux in the gap 302. This magnetizes the magnetic
layer 298 in the vicinity of the gap. Then as the head moves
another incremental distance another pulse is applied, or no pulse
is applied.
The magnetic strip is thus magnetized in a pattern of magnetized
spots, which can be read by moving the same head along the strip
and detecting the minute voltages induced in the windings. This is
all conventional.
What we propose is to have a plurality of fixed spaced heads like
300 in contact with the strip 298 in selected spacing. Then by
applying pulses of current to the heads in a selected pattern,
either sequentially or simultaneously, while the heads are
stationary with respect to the card, a pattern of magnetized spots
will be generated.
This pattern of spots can be read by leaving the heads in contact
and relatively oscillating the card 280 or the heads, in accordance
with arrow 308B. Each time that the head passes over a magnetized
spot is will generate in the coil a pulse or a small wavelet of
voltage.
As shown in FIG. 7, the record and read heads can be simplified to
a simple linear core pressed against the strip. The ends in contact
with the strip 298 can be points. The other ends of the cores can
go to a magnetic yoke, for flux return, etc. as is well known in
the art. Here again the strip is magnetized by passing a pulse of
current through the coils 322 while the card and heads are
stationary, at the midpoint of the oscillation 308B. Then by
relatively oscillating the card, an a.c. voltage will be generated
in the coils.
If desired, the polarity of the current pulses can determine
whether a bit recorded is a "1" or a "0". Then the phase of the
generated voltage will be an indicator of the "1" or "0".
Reference is now made to FIGS. 8 and 9 and 10, which indicate
schematically the use of holograms as the unique authenticating
master coded patterns. FIG. 8 illustrates schematically apparatus
for the preparation of a hologram, using a spot pattern object, and
an amplitude coded reference beam.
The laser 352 provides a beam 354 of coherent radiation. The beam
splitter 356 provides two coherent beams, 358 which becomes the
object beam, and 370 which becomes the reference beam. The object
beam 358 passes through optics 360 to provide an expanded
collimated beam 362 which passes through object plate 364.
Object plate 364 can be a fixed plate of any desired transparency
pattern. Or it can be a transparent spot pattern. Also, it can be a
fixed plate which would be the same for all holograms, or it can be
a different plate, or a series of plates, such as on a film strip,
380, having supply and takeup reels 364A, 364B, for example, as
would be well known to the man skilled in the art. As a type of
hologram system, reference is made to U.S. Pat. No. 3,560,071.
The coded object beam then passes through optics 365 located at its
focal length from the object plate 364, to form beam 366, which
then impinges on a photosensitive web or film 368. The optics 365
can be conventional to provide a Fresnel, or a Fraunhofer hologram,
as shown in FIG. 8, as is well known in the art.
The beam 370 is reflected by means of mirror 372 to form beam 373,
which passes through optics 374 to form expanded collimated beam
376, which then passes through coding mask 380. The mask or film
380 is shown in FIG. 9, which is a film strip having a column of
frames 384A, 384B, 384C etc, with a corresponding series of frames
386A, 386B, 386C etc. The frames 384 are reference beam coding
transparencies, each having a unique pattern of transparent and
opaque areas. These will be used to code the reference beams.
Corresponding to each unique coding pattern is a line or bit
pattern which represents an index of the various coding patterns.
For example, when a card is presented to the access authentication
apparatus, the index number on the card will control the selection
of the corresponding coding pattern of a reference beam, and so on.
Servo apparatus for selecting the proper frame corresponding to the
particular index number is well known and need not be described
further.
The coding patterns of the reference beams can be amplitude or
phase coding patterns, as are well known. Also the optics used can
provide Fresnel or Fraunhofer holograms, as are well known in the
art.
It is well known in optics, that the simultaneous irradiation of a
photographic film with a coherent object beam and reference beam
will provide a stationary interference pattern of the two coherent
beams, which interference pattern is recorded on the film as a
hologram. When the film is developed it becomes a hologram, which
can be replaced at its original position 368. When irradiated by
the same reference beam 392 alone, (the object beam being cut off
by mask 359) will reconstruct an image of the original object plate
or film 364. One image can be viewed by eye, as is well known
and/or the other image can be brought to a real focus. If the
object 364 is a pattern of bright spots, then the reconstruction
will be the same pattern of bright spots. These spots can be
detected by a corresponding pattern of photocells, sensors, or
receivers 396, as is well known in the art. By the signals created
in the sensors 396, the pattern of spots can be automatically read
and identified, and so on, and compared with the pattern of the
original object plate.
In this invention it is an object to provide an access card which
has an index, which is machine readable, and a transparent or
reflective hologram. The hologram is prepared in an apparatus like
FIG. 8, with a unique coded reference beam made by a specific frame
384, corresponding to the index number corresponding to that on the
card.
When the card is presented for access, the index is read, the
particular reference beam coding pattern 384 is selected and placed
in position to code beam 392. The card is positioned at 368 and the
coded reference beam 392 impinging on the hologram on the card will
reconstruct the object pattern image 394 which is focussed by lens
395 on the sensors 396, and authenticate the card. If the proper
pattern is not authenticated, then access is not granted, and the
card may be confiscated.
So far we have discussed several unique elements of the system:
(a) the unique coding pattern of the reference beam. This is
selected from a bank or coding patterns by use of the index read
from the card.
(b) the unique hologram which was recorded by the unique coded
reference beam, the coding pattern of which corresponds in the bank
to the index on the card.
(c) the spot which is the object coding pattern. A plurality of
unique object patterns can be provided. When the card is presented
for access authentication, the reconstructed object pattern must
correspond to a preselected pattern. For example, the user may
punch into a data entry device 268 a coded number of PIN number
which can be compared to the reconstructed pattern.
FIG. 10 illustrates another embodiment in which the card 404
carries a unique machine readable index, a reference beam coding
pattern 410, and a hologram 408 constructed using that reference
beam coding pattern 410, and an object beam coded by a unique spot
pattern 364 of FIG. 8, selected from a bank, such as a film strip
similar to that of FIG. 9.
When the card 404 is presented for authentication, it is positioned
in a laser beam 406 provided by laser 400 and optics 402. This
produces a coded reference beam 412, which is reflected from
mirrors 414,416, and passes through optics 418, and as beam 422
impinges on the hologram 408. This reconstructs the hologram and an
image is formed by beam 424, in the form of a spot pattern which
falls on a bank of sensors 426. This pattern is then compared to
the pattern stored in the bank corresponding to the index number on
the card, or compared to a PIN number entered into 268 and so
on.
It will be clear that the embodiments of FIGS. 4, 8 and 10 each
have unique advantages. FIG. 4, for example, can be presented at a
remote terminal which is simple in construction and can be
connected to the control apparatus by wires. The index and the
magnetic patterns can easily be copied. However, the apparatus of
FIG. 4 has the advantage that the magnetic pattern can be changed
to a different unique pattern each time the card is presented.
Since the card can be presented as frequently as desired, this
feature effectively prevents use of a nonauthorized facsimile card.
Furthermore the magnetic card reading means is simple, such that a
very simple and compact assembly can be provided, that will read
the card and write its new number. Such a simple accessory can be
carried in a brief case, etc. and utilized in conjunction with
telephone lines to a remote control point. By this means,
authenticated access can be gained to confidential information, or
data from a computer, etc.
With the apparatus of FIGS. 8,10, the card has the advantage that
the hologram pattern is unique, and cannot readily be copied. In
that sense it has greater security than the magnetic card of FIG.
4. However, the cards of FIGS. 8 and 10 require more extensive card
reading and authenticating apparatus, and may require a bank of
reference beam coding patterns, which means that the apparatus of
FIG. 8 is most effective when the point at which access is desired
is at the location of the bank.
On the other hand, the card of FIG. 10 is not readily copied and
does not require a bank at the point where access is desired. The
reconstructed point pattern can be scanned and transmitted by wire
to the remote bank location, and so on.
It will be clear that the card can be a physical, stiff card of
paper, plastic or metal, or it can be a key having a unique pattern
such as is designed to open a specific lock, or a token of any
type. The key can be of nonmagnetic metal, with the pattern serving
as the unique index. A relieved portion of the flat surface of the
key can be coated with magnetic material, on which a unique bit
pattern can be recorded. Such a key can be used with the apparatus
of FIG. 7 for example, with FIG. 4. This can be used for safe
deposit boxes, automobile locks, hotel rooms, etc.
The configuration of FIG. 8 represents a complete hologram reading
and recording system, where both the object beam 366 can be coded
by means 364, and the reference beam 392 can be coded by means 378.
Using the coded object and reference beams a hologram 368 is
recorded, and, after chemical development, is mounted in the access
card. The unique index on the card can be that corresponding to the
storage address of the coding pattern 364 of the object beam, or
the reference beam coding pattern 378. To reconstruct the hologram
only that part of the system of FIG. 8 that includes the reference
beam 392, the card hologram 368 and the image sensors 396 are
required. The pattern on the image sensors will correspond to the
particular object beam coding pattern used.
In the system of FIG. 10, the reference beam coding pattern used to
record and reconstruct the hologram is on the same card 404 as the
hologram. In this system, the unique index would correspond to the
particular coding pattern of the object beam.
It is well known in optical holography that with selected different
object beams, and a selected reference beam, different holograms
can be recorded with the same reference beam, provided that the
angle at which the reference beam reaches the photo sensitive
medium is different for each hologram. In FIG. 10, the dashed line
404A is used to represent this factor of angle, by rotating the
plane of the hologram 408 to different angles of azimuth and/or
elevation. These angles can correspond to specific PIN numbers that
can be punched in to the data entry means 268 to set the angle of
the film, while recording the hologram in FIG. 8, a and in
reconstructing the hologram in FIG. 10.
The various possible factors that can be used are:
(a) coding spot pattern of the object beam and comparing the
reconstructed image with the object beam coding pattern.
(b) coding spot pattern of the reference beam, and selecting the
proper coding pattern by the index to reconstruct the object
pattern.
(c) as in (b) and comparing the object coding pattern with the
reconstructed image.
(d) mounting the reference beam coding pattern and the hologram on
the card, and comparing the image with the object coding
pattern.
In FIG. 4, we have taught the procedure of changing a unique number
on a card and in the bank each time a card is authenticated. In the
prior art it is customary to use an index number on a card in
cooperation with a PIN number punched in by means of data entry
means 268. As part of this invention we utilize this basic system
and add to it the feature of changing the PIN number each time the
card is used and authenticated. This would call for a visual
indicator like 452 of FIG. 4 which is set by signals received over
dashed line 450 from line 252. The card user would read the new
number, and make a record, if necessary, for future use, and on the
next time the card is used, the new PIN number would be entered,
and so on. A new PIN number can of course constitute an old PIN
number, with the same digits arranged in a different order, and so
on.
In the system of FIG. F, it will be clear that as the unique master
coded magnetic bit pattern or number is changed on the card 224 and
in the bank 214 each time the card is authenticated, a record can
be kept of each of the numbers so that the complete sequence of
numbers can be recalled as may be desired.
* * * * *